DIRECT OBSERVATION OF LIGAND MIGRATION IN THE REVERSIBLE ADDITION OF TRIMETHYLPHOSPHINE TO 1,2-MO2(CH2PH)2(O-I-PR)4 AND STRUCTURAL CHARACTERIZATION OF (PME3)(PHCH2)2(I-PRO)MO-EQUIVALENT-TO-MO(O-I-PR)3 AND 1,2-MO2(CH2PH)2(O-I-PR)4(DMPM), WHERE DMPM = BIS(DIMETHYLPHOSPHINO)METHANE

被引:17
作者
CHISHOLM, MH [1 ]
FOLTING, K [1 ]
HUFFMAN, JC [1 ]
KRAMER, KS [1 ]
TATZ, RJ [1 ]
机构
[1] INDIANA UNIV,CTR MOLEC STRUCT,BLOOMINGTON,IN 47405
关键词
D O I
10.1021/om00060a018
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
Addition of PMe3 (1-2 equiv) to hydrocarbon solutions of 1,2-Mo2(CH2Ph)2(O-i-Pr), (I) at 22-degrees-C leads to an equilibrium mixture of I, free PMe3, and (PMe3)(PhCH2)2(i-PrO)Mo=Mo(O-i-Pr)3 (II). Compound II is an orange crystalline solid that loses PMe3 upon heating in vacuo (slowly at room temperature and rapidly at +50-degrees-C) with the regeneration of I. Addition of 2 equiv of PMe3 to I in toluene-d8 at -80-degrees-C yields a bisphosphine adduct (PMe3)(PhCH2)(i-PrO)2Mo=Mo(O-i-Pr)2(CH2Ph)(PMe3) that yield II upon warming to +20-degrees-C by way of an intermediate. When the solution is cooled, an unsymmetrical bisphosphine adduct (PMe3)(PhCH2)2(i-PrO)Mo=Mo(O-i-Pr)3(PMe3) is formed at -80-degrees-C. The latter forms II reversibly by PMe3 loss upon warming. Addition of dmpm to I in hexane or toluene (at -60-degrees-C) yields 1,2-Mo2-(CH2Ph)2(O-i-Pr)4(mu-dmpm) (III), where dmpm = bis(dimethylphosphino)methane. Compound III was isolated at -25-degrees-C by crystallization. In toluene-d8 and at room temperature, the H-1 and P-31 NMR spectra indicate the presence of an isomeric form of III, (eta1-dmpm)(PhCH2)2(i-PrO)Mo=Mo(O-i-Pr)3. Addition of dmpe (1 equiv) to hydrocarbon solutions of I yields an insoluble crystalline material MO2(CH2Ph)2(O-i-Pr)r(dmpe) (IV), where dmpe = 1,2-bis(dimethylphosphino)ethane. Compound IV is sparingly soluble in tetrahydrofuran and upon photolysis in the presence of additional dmpe compound IV is converted to Mo2(O-i-Pr)4(dmpe)2 and bibenzyl. Crystal data: for II at -159-degrees-C a = 16.779 (3) angstrom, b = 10.104 (1) angstrom, c = 19.555 (4) angstrom, beta = 90.59 (10)-degrees, Z = 4, d(calcd) = 1.38 g cm-3 and space group P2(1)/c; for III at -168-degrees-C a = 14.952 (2) angstrom, b = 29.252 (4) angstrom, c = 17.637 (2) angstrom, beta = 111.05 (1)-degrees, Z = 8, d(calcd) = 1.38 g cm-3, and space group P2(1)/n.
引用
收藏
页码:4029 / 4036
页数:8
相关论文
共 26 条
[1]  
ADAMS RD, 1989, METAL METAL BONDS CL
[2]  
APPLETON TG, 1972, COORDIN CHEM REV, V10, P353
[3]  
ARNOLD DR, 1983, J CHEM SOC CHEM COMM, V1, P32
[4]   USE OF ISOTOPE CROSSOVER EXPERIMENTS IN INVESTIGATING CARBON-CARBON BOND-FORMING REACTIONS OF BINUCLEAR DIALKYLCOBALT COMPLEXES [J].
BERGMAN, RG .
ACCOUNTS OF CHEMICAL RESEARCH, 1980, 13 (04) :113-120
[5]   PREPARATION AND CHARACTERIZATION OF THE HEPTACHLOROBIS(TETRAHYDROFURAN)DITUNGSTATE AND OCTACHLORO(TETRAHYDROFURAN)DITUNGSTATE ANIONS - [PH4P][W2CL7(THF)2] AND [PH4P][W2CL8(THF)] [J].
BERGS, DJ ;
CHISHOLM, MH ;
FOLTING, K ;
HUFFMAN, JC ;
STAHL, KA .
INORGANIC CHEMISTRY, 1988, 27 (17) :2950-2954
[6]   THE TUNGSTEN TUNGSTEN TRIPLE BOND .17. MIXED AMIDO PHOSPHIDO COMPOUNDS OF FORMULA M2(PR2)2(NME2)4 - COMPARISONS OF AMIDO AND PHOSPHIDO LIGATION AND BRIDGED AND UNBRIDGED ISOMERS [J].
BUHRO, WE ;
CHISHOLM, MH ;
FOLTING, K ;
HUFFMAN, JC ;
MARTIN, JD ;
STREIB, WE .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (02) :557-570
[7]   HOS3(CO)10CH3 - NMR EVIDENCE FOR A C..H..OS INTERACTION [J].
CALVERT, RB ;
SHAPLEY, JR .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1978, 100 (24) :7726-7727
[8]   REACTIONS OF METAL-METAL MULTIPLE BONDS .8. FORMING MO-MO QUADRUPLE BONDS BY REDUCTIVE ELIMINATION (ALKYL GROUP DISPROPORTIONATION) IN THE REACTIONS OF 1,2-MO2R2(NME2)4 COMPOUNDS (M=M) WITH CARBON-DIOXIDE AND 1,3-DIARYLTRIAZINES [J].
CHETCUTI, MJ ;
CHISHOLM, MH ;
FOLTING, K ;
HAITKO, DA ;
HUFFMAN, JC .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1982, 104 (08) :2138-2146
[9]   THE MOLYBDENUM-MOLYBDENUM TRIPLE BOND .11. 1,1-DISUBSTITUTED AND 1,2-DISUBSTITUTED DIMOLYBDENUM COMPOUNDS OF FORMULA MO2X2(CH2SIME3)4 (M=M) - OBSERVATION OF ROTATION ABOUT THE TRIPLE BOND [J].
CHISHOLM, MH ;
FOLTING, K ;
HUFFMAN, JC ;
ROTHWELL, IP .
ORGANOMETALLICS, 1982, 1 (02) :251-259
[10]  
CHISHOLM MH, 1984, J AM CHEM SOC, V106, P5385, DOI 10.1021/ja00330a077